Field
Exemplary embodiments relate to a liquid crystal display and a method for manufacturing the same.
Discussion of the Background
A flat panel display may be used as a display device. Various display devices, such as a liquid crystal display, an organic light emitting diode display, a plasma display, an electrophoretic display, and an electrowetting display may be used.
The liquid crystal display (LCD) is one of the flat panel displays most widely used currently. Such LCDs include two sheets of display panels in which an electrode is formed and a liquid crystal layer interposed therebetween. In the liquid crystal display, a voltage is applied to the electric field generating electrode to generate an electric field in the liquid crystal layer and the orientation of liquid crystal molecules of the liquid crystal layer is determined and polarization of incident light is controlled based on the generated electric field to display an image.
Among the liquid crystal displays, a liquid crystal display which is currently in wide use has a structure in which electric field generating electrodes such as a pixel electrode and a common electrode are provided in two display panels, respectively. Among those, mainstream liquid crystal displays have a structure in which one display panel (hereinafter, referred to as ‘thin film transistor array panel’) is arranged with a plurality of thin film transistors and pixel electrodes in a matrix form and the other display panel (hereinafter, referred to as ‘common electrode display panel’) is formed with color filters (e.g., red, blue, and green), and a front surface of the other display panel is covered with a common electrode.
The liquid crystal display has a misalignment problem since it is difficult to accurately align the pixel electrode and the color filter which are formed in different display panels. To address the above problem, a structure in which a light blocking member is formed in the display panel in which the pixel electrode and the thin film transistor are formed has been proposed. In this case, the color filter may also be formed in the display panel in which the pixel electrode is formed.
A gap between the liquid crystal layers interposed between the two display panels is called a cell gap. The cell gap affects the operational characteristics of a liquid crystal display such as the response speed, contrast ratio, viewing angle, luminance uniformity, and the like. However, when the cell gap is non-uniform, a uniform image is not displayed over the whole screen, and thus image quality may deteriorate. Therefore, to keep a uniform cell gap over the whole region on a substrate, a spacer is formed on one side of the two substrates. A column spacer (CS) has been mainly used as the spacer.
For simplification, a light blocking member, such as a black matrix, and the spacer may be simultaneously formed. To simultaneously form the light blocking member, the spacer, and the like, there is a need to form a multi step element.
However, it is difficult to stably form a step between a main column spacer and a sub-column spacer due to the lack of a margin in material exposure. As a result, a column spacer and a sub-column spacer are formed with similar heights, and are highly likely to cause a smear phenomenon and create an active unfilled area (AUA) which prevents liquid crystal from filling in part of the liquid crystal display panel.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.